Amphibious Assault Ships - LHD/LHA(R)

Description

The largest of all amphibious warfare ships; resembles a small aircraft carrier; capable of Vertical/Short Take-Off and Landing (V/STOL), Short Take-Off Vertical Landing (STOVL), Vertical Take-Off and Landing (VTOL) tilt-rotor and Rotary Wing (RW) aircraft operations; contains a well deck to support use of Landing Craft, Air Cushion (LCAC) and other watercraft (with exception of the first two LHA(R) class ships, LHA 6 and LHA 7, which have no well deck). LHA 8 will feature a well deck.

FeaturesModern U.S. Navy Amphibious Assault Ships project power and maintain presence by serving as the cornerstone of the amphibious ready group (ARG)/expeditionary strike group (ESG). A key element of the Sea Power 21 pillars of Sea Strike and Sea Basing, these ships transport and land elements of the Marine expeditionary unit (MEU) or Marine expeditionary brigade (MEB) with a combination of aircraft and landing craft.

The America-class LHAs and Wasp-class LHDs provide the Marine Corps with a means of ship-to-shore movement by helicopter in addition to movement by landing craft. LHAs (and later LHDs) have been participants in major humanitarian-assistance, occupation and combat operations in which the United States has been involved. Such operations have included participating as launch platforms for Marine Corps expeditionary forces into Afghanistan during Operation Enduring Freedom in 2001 and 2002, Iraq in Operation Iraqi Freedom in 2003 and humanitarian support after the catastrophic Tsunami in 2004. During Operation Iraqi Freedom, two LHDs served as "Harrier carriers," launching an air group of AV-8B attack aircraft against targets inside Iraq. In 2004, LHDs were used to transport thousands of Marines and their equipment to Iraq and Afghanistan for combat operations. Post Hurricane Katrina support was provided in New Orleans by LHD 7 (Iwo Jima) where thousands of police, fire and rescue personnel were hosted onboard during recovery operations and Iwo Jima operated as the central command and control hub.

USS Makin Island (LHD 8) was delivered to the Navy in April 2009 and is the first U.S. Navy amphibious assault ship to be equipped with both gas turbines and an auxiliary propulsion system (APS) instead of steam boilers. The APS uses two induction-type auxiliary propulsion motors (APM) powered from the ship's electrical grid rather than relying on main propulsion engines to power the ship's shaft, which are less efficient at lower speeds. Instead of using its gas turbines, which are less efficient at lower speeds, the ship will be able to use its APS for roughly 75 percent of the time the ship is underway. The entire propulsion and electric system is controlled by a comprehensive machinery control system that also controls and monitors damage control, ballasting and de-ballasting, fuel fill and auxiliary machinery. The machinery control system allows the ship to switch from gas turbine to electric propulsion on the fly. It is fully distributed, accessible from multiple locations, and every console provides full system control and monitoring capabilities of the entire engineering plant.

USS America (LHA 6), along with the future USS Tripoli (LHA 7) are LHD variants optimized for aviation capability. The propulsion plant and electrical distribution and auxiliary systems designed and built for USS Makin Island are also used aboard USS America and future USS Tripoli, the first ships in the LHA Replacement Program. USS America was delivered to the U.S. Navy on April 10, 2014 and the future USS Tripoli is currently under construction at Huntington Ingalls Industries (HII) in Pascagoula, Mississippi and is expected to join the fleet in 2018. LHA 6 and LHA 7, commonly referred to as Flight 0 ships, contain key differences from the LHD class to include: an enlarged hangar deck, enhanced aviation maintenance facilities, increased aviation fuel capacity, additional aviation storerooms, removal of the well deck, and an electronically reconfigurable C4ISR suite. On June 30, 2016, Huntington Ingalls Industries was awarded a contract for planning, advanced engineering and procurement of long lead time material. An option for the detail design and construction of LHA 8 was awarded in June 2017, which will be the first Flight I ship, and will reincorporate a well deck to increase operational flexibility. The USS America (LHA 6) class ships replace the original five Tarawa-class LHAs, which have all been decommissioned. USS Belleau Wood (LHA 3) was decommissioned in October 2005, followed by USS Saipan (LHA 2) in April 2007, USS Tarawa (LHA 1) in March 2009, USS Nassau (LHA 4) in March 2011 and USS Peleliu (LHA 5) in March 2015.

BackgroundAmphibious warships are designed to support the Marine Corps tenets of Operational Maneuver From the Sea (OMFTS) and Ship to Objective Maneuver (STOM). They must be capable of sailing in harm's way and enable rapid combat power buildup ashore in the face of opposition. Because of their inherent capabilities, these ships have been and will continue to be called upon to also support humanitarian and other contingency missions on short notice. The United States maintains the largest and most capable amphibious force in the world.

The Wasp-class LHDs are currently the largest amphibious ships in the world. The lead ship, USS Wasp (LHD 1) was commissioned in July 1989 in Norfolk, Virginia. The delivery of LHA Replacement or LHA(R) America-class ships is the next step in the incremental development of the "Big Deck Amphib." American-class ships are designed to accommodate the Marine Corps' future Air Combat Element (ACE) including F-35B Joint Strike Fighter (JSF) and MV-22 Osprey with additional aviation maintenance capability and increased fuel capacities, while also providing additional cargo stowage capacities and enabling a broader, more flexible Command and Control capability.

Program StatusLHDs 1-8 and LHA 6 are in service. The Navy awarded a contract for detail design and construction for LHA 7 to HII on May 31, 2012. The ship started fabrication on July 15, 2013. LHA 8 starts fabrication in the fall of 2018.